JP4580617B2 - Large manipulator with anti-vibration device - Google Patents

Abstract

The heavy manipulator has a frame supporting a mast block which is rotatable about a vertical axis, provided with a handling mast having at least 3 relatively pivoted mast arms (23-27), operated via respective drive units (34-38) coupled to a control device, responding to remote-control commands and associated setting elements (68-76). At least one of the drive units or mast arms has a sensor (84,86) for detecting mechanical oscillation, coupled to an evaluation unit (82) providing a damping signal for the associated setting element. An independent claim for a method for damping mechanical oscillation of a heavy manipulator mast is also included.

Description

[0001]
The present invention is arranged in a trapezoidal rack on the mast support rotatable about a lead straight direction of the rotation axis, is assembled from at least three mast arms, a bent mast is configured as a frequency distribution mast, The bending masts , wherein the mast arms are pivotably pivoted in pairs around horizontal bending axes parallel to each other with respect to adjacent mast supports or mast arms, respectively, by drive assemblies ; can far隔操operation, and a buffer means for buffering a control device for controlling the movement of the mast with the adjusting member are attached to each drive assembly, the mechanical vibration of the bending mast The present invention relates to a large manipulator, particularly a large manipulator for a concrete pump.
[0002]
The bending mast of this type of large manipulator is structurally an elastic vibration system, and when excited, it becomes a natural vibration. When such vibration is resonantly excited, the tip of the mast vibrates with an amplitude of 1 meter or more. The excitation of vibrations is caused, for example, by the pulsating motion of the concrete pump and the consequent acceleration and deceleration of the concrete column pushed by the transport pipe. As a result, the concrete cannot be evenly distributed and the operator operating the end hose is at risk. In order to prevent this, a known concrete pump with a bending mast (German Patent Publication No. 19503895) stabilizes the level of the mast tip with respect to the stationary horizontal reference plane within a preset changeable range. It has been proposed to use an attitude control circuit that allows For this purpose, a sensor device is provided, and a coordinate adjustment drive unit for correcting and displacing the mast tip or the terminal hose can be controlled via an output signal of the sensor device. However, this procedure has been found to be costly and does not necessarily lead to the desired result. The arm motion detection sensor device necessary for the control responds only when the motion is performed, that is, the response is too slow. Therefore, sufficient control quality cannot be obtained.
[0003]
It is an object of the present invention to provide an apparatus and method that allows optimal mast cushioning with simple means.
In order to solve the above-mentioned problems, the present invention proposes a combination of constituent features described in claims 1 and 14 . Other advantageous configurations of the invention are evident from the dependent claims.
[0004]
The basic idea of the solution according to the invention is to measure a time-dependent measure derived from mechanical vibrations of the mast arm in at least one of the drive assemblies or in the mast arm attached thereto, and to buffer it. It is to be processed by the unit to form a dynamic buffer signal and to be interrupted by an adjustment member that controls the drive assembly.
[0005]
According to a preferred embodiment of the present invention, when the drive assembly is configured as a hydraulic cylinder, by measuring the time dependence pressure difference between the bottom side and the piston rod side of the hydraulic cylinder as a measured quantity, with a buffer unit Sort to form a buffer signal. In the selection of the signal, it is appropriate to filter the measured quantity dynamic component above a predetermined limit frequency in the buffer unit and to phase shift and / or amplify to form a buffer signal. The limiting frequency is preferably set to 0.2 Hz to 10 Hz, depending on the mechanical natural frequency of the mast arm. May go comprising, limit frequency of the high-pass filter, it is necessary to select somewhat lower than the natural frequency of the mast arm. As mast cushioning without position control may cause the mast tip to shift and may be undesirable, according to an advantageous alternative of the invention, the end of the bending mast is delivered to the operating position. By measuring the inclination of the arm or the distance from the ground at a predetermined time interval and comparing it with a pre-stored target value, if a deviation from the target value occurs, control at least one of the adjustment members Additional control of the bending mast.
[0006]
In order to carry out the method according to the invention described above, according to the invention, at least one of the drive assembly or the mast arm is provided with at least a time-dependent measurement quantity derived from the mechanical vibration of the mast arm. It is proposed that one sensor and a buffer unit for generating a buffer signal, which is arranged downstream of the at least one sensor and whose output side is connected to an attached adjusting member, are attached.
[0007]
According to an advantageous configuration of the invention, each drive assembly has a double-acting hydraulic cylinder, and each double-acting hydraulic cylinder is connected with pressure oil via a respective proportional switching valve forming an associated adjusting member. Can be energized. In this case, according to the present invention, the piston rod side end and the bottom side end of at least one double acting hydraulic cylinder of the double acting hydraulic cylinder are preferably connected via a comparator or a difference detector. One pressure detection sensor (pressure pickup) is connected to each buffer unit . Advantageously, the buffer unit has a high-pass filter which is configured in analog or digital form. Advantageously, the limiting frequency of the high-pass filter belonging to each mast arm can be adjusted separately depending on the natural frequency of the respective mast arm. A typical limiting frequency of the high-pass filter is 0.2 Hz to 10 Hz.
[0008]
According to an advantageous configuration of the invention, each high-pass filter is formed by a low-pass filter with an input interrupting the output of the comparator via a comparator. In order to avoid overshoot, each high-pass filter has an aperiodic transfer function. Further, an evaluation / safety circuit or an evaluation / safety routine is arranged downstream of each high-pass filter. In the evaluation / safety circuit or the evaluation / safety routine, the input side can be energized by the output signals of both pressure detection sensors.
[0009]
According to an advantageous configuration of the invention, the control device comprises a microcontroller with a coordinate setter for controlling the adjustment member, the microcontroller moving the input side through a bus system and a remote control device. It is possible to energize with the movement data for use, and a transmitter for auxiliaryly forming a buffer unit is attached to each adjustment member, and the transmitter can be energized with a measured amount belonging to the mast arm on the input side. With this procedure, the bending mast is controlled by the pump operator based on the travel data preset via the remote control device, while the mast buffering is automatically performed during the movement process and when the bending mast is in the operating position. . In this case, the buffer unit is coupled to the control circuit of the individual drive assembly. It is expedient for each transmitter to be configured as a second order high-pass filter, whose transfer function has an aperiodic behavior. This ensures that there is no additional failure in the system via the filter and its transmitter. Therefore, the buffer unit according to the present invention is characterized in that an independent buffer unit is attached to each mast arm.
[0010]
As the pressure detection sensor, for example, a diaphragm sensor or a piezoelectric sensor is conceivable. When a micro controller is provided for these sensors, a measurement converter provided with an analog-digital converter is attached.
[0012]
Embodiments of the present invention are illustrated in the drawings and will be described in detail below. The automatic concrete pump 10 can rotate around a conveying vehicle 11, a concentrated material pulsating pump 12 configured as, for example, a two-cylinder piston pump, and a height axis 13 fixed to the vehicle, and carries a concrete conveying pipe 16. And a distribution mast 14 used as a carrier. Liquid concrete that is continuously charged into the charging container 12 while it is being made into concrete is transported to a concrete use site 18 that is disposed at a position away from the current position of the transport vehicle 11 via a concrete transport pipe 16. Is done.
[0013]
The distribution mast 14 has a mast support 21 that can be rotated around the height axis 13 by using a hydraulic rotation driving unit 19, and a bent mast 22 that can be rotated on the mast support 21. The bending mast 22 can be continuously adjusted with respect to the height difference between the conveying vehicle 11 and the concrete use point 18 and the variable reachable distance. In the case of the illustrated embodiment, the bending mast 22 has five mast arms 23 to 27 that are pivotally connected to each other, these mast arms being parallel to each other and perpendicular to the height axis 13 of the mast support 21. It is pivotable about an extending axis 28-32. The bending angles ε ₁ to ε ₅ (FIG. 2) of the bent pivot portions formed by the pivot axes 28 to 32 and the mutual arrangement of the bent pivot portions are aligned with each other. The distribution mast 14 can be placed on the transport vehicle 11 in a space-saving transport arrangement corresponding to the state. By programmatically controlling the operation of the drive assemblies 34-38 assigned to the individual pivot axes 28-32, the bending mast 22 can be moved at various distances and / or between the concrete use point 18 and the current position of the conveying vehicle. The difference can be developed (FIG. 2).
[0014]
The mast operator controls the mast movement using the wireless remote control unit 50, for example, and guides the mast tip 33 provided with the terminal hose 43 to a position beyond the concrete use area. The end hose 43 is typically 3 m to 4 m long, is pivotally suspended in the region of the mast tip 33 and is inherently elastic so that the hose operator can use the concrete hose 18 at the end of the end hose. Can be held at a preferred position.
[0015]
The remote operation unit 50 has a plurality of operation mechanisms 60 configured as control levers, and these operation mechanisms 60 can be adjusted forward and backward in two adjustment directions perpendicular to each other while emitting control signals. The control signal is transmitted via a wireless path 61 to a wireless receiver 62 that is fixed to the carrier vehicle. The wireless receiver 62 is connected on the output side to a microcontroller 52 via a bus system 63 configured, for example, as CAN-BUS. ing. The microcontroller 52 has a coordinate setter 64 which is controlled by a computer in particular. The coordinate setter 64 transfers the movement data transmitted from the wireless receiver 62 to the drive assemblies 19, 6, 13, 28 to 32. Convert to coordinate signals for 34-38. In addition, the magnitude of the displacement of the operation mechanism 60 may be converted into a speed determination signal. The operation of the drive assemblies 34 to 38 is performed via an adjusting member configured as a proportional switching valve. These adjusting members are connected to the bottom side and the piston rod side of the drive assemblies 34 to 38 whose outlet pipes 78 and 80 are configured as double acting hydraulic cylinders. The drive assembly 19 for the mast support 21 is configured as a hydraulic rotation drive unit and is controlled via an adjustment member 66. In addition to the control via the coordinate setting device 64 that decodes the traveling data sent, for example, as cylinder coordinates and correspondingly converts them (German Patent Publication No. 4306127), the individual drive assemblies 19, 34 to 36 may be controlled via the direct operation mechanism 60 and the attached adjusting members 66 to 76.
[0016]
The bending mast 22 forms a vibration system together with the transport vehicle 11. This oscillating system may be forced to vibrate during operation of the pulsating concentrated material pump 12. The vibration displaces the mast tip 33 and the terminal hose 43 suspended from the mast tip 33, and has an amplitude of 1 meter and a frequency of 0.5 Hz to several Hz.
[0017]
In order to prevent an increase in resonance vibration of the bending mast 22, the microcontroller 52 further includes a plurality of buffer units 82 controlled by software. The buffer unit 82 is connected to the pilot input portion of each adjustment member 68-76. The buffer unit 82 is energized on the input side with a time-dependent measurement derived from the mechanical vibration of the respective mast arms 23-27. For this reason, in the illustrated embodiment, pressure sensors 84 and 86 are arranged at the bottom side end portions and piston rod side end portions of the drive assemblies 34 to 38 configured as hydraulic cylinders, respectively. The output parts p _s and p _b of the pressure sensors 84 and 86 are connected to a comparator 88, which generates a time-dependent measurement signal corresponding to the pressure difference Δp (t) = p _s −p _b . The measurement signal Δp (t) is sent to the digital high-pass filters 90 and 92 at a predetermined time period. In the embodiment shown in FIG. 4, the high-pass filter is formed by a digital low-pass filter 90 having a comparator 92 on the downstream side, and the comparator 92 further receives an input signal of the low-pass filter 90. The cut-off frequency of the high-pass filters 90, 92 is set separately for each mast arm 23-27 and is selected somewhat less than the mechanical natural frequency of the mast arm. The buffer unit 82 further includes an evaluation / safety algorithm 94 disposed downstream of the digital high-pass filters 90, 92. The evaluation / safety algorithm 94 is used to set an amplification degree necessary for image stabilization. It is. Furthermore, the safety limit value of the mast arm is also monitored by this safety algorithm, for example via an end stop controller. For this purpose, the absolute pressure values p _s and p _b measured by the pressure sensors 84 and 86 on the bottom side and the piston rod side may be evaluated.
[0018]
Since the stopper of the bending axis is not controlled, it is necessary to prevent the bending mast 22 from shifting due to structural tolerances. This is the case when the bending mast is in the operating position during pump operation. This shift can be monitored and corrected. Therefore, as can be seen from FIGS. 2 and 4, the last mast arm 27 is provided with a solid angle detection sensor 94 or a distance detection sensor configured as an inclination detection sensor, and a target value storage memory 96. As a result, the current angular position of the mast tip 33 or the distance from the ground can be stored in the target value storage memory 96 at each operating position, that is, at the end of each traveling process. By comparing the current value with the stored target value, a shift is detected in the subsequent time passage, and correction can be made, for example, via the coordinate setting device 64 by controlling at least one of the adjusting members 68 to 76. it can.
[0019]
In summary, it is as follows.
The present invention relates to large manipulators, particularly large manipulators for concrete pumps. The large manipulator according to the invention has a bent mast 22 which is assembled from at least three mast arms 23 to 27 and is preferably configured as a concrete distribution mast. The mast arms 23 to 27 of the bending mast can be pivotally rotated around horizontal bending axes 28 to 32 parallel to each other by drive assemblies 34 to 38, respectively. Furthermore, there are control devices 50, 62, 52 for controlling the movement of the mast using adjusting members attached to the individual drive assemblies 34 to 38 and buffer means for buffering mechanical vibration of the bending mast. Is provided. In order to achieve an effective mast damping in a simple manner, the invention advantageously derives from the mechanical vibrations of the mast arm in each drive assembly 34-38 or in the associated mast arms 23-27. It is proposed to measure the measured time-dependent measurement and process it with a buffer unit to form a dynamic buffer signal and to interrupt the adjusting member that controls the drive assembly.
[Brief description of the drawings]
FIG. 1 is a side view of an automatic concrete pump showing a bent mast in a folded state.
2 is a view of the automatic concrete pump of FIG. 1 when the bending mast is in the operating position.
FIG. 3 is a schematic diagram of a control device for controlling mast movement and buffering action.
FIG. 4 is a flowchart of a mast buffer software transmitter included in a microcontroller.

Claims (17)

The mast support (21) arranged on the stand (11) and rotatable around the vertical rotation axis (13) and at least three mast arms (23 to 27) is assembled and configured as a distribution mast. Bending mast (22), wherein the mast arms (23-27) are parallel to each other by the drive assemblies (34-38) with respect to the adjacent mast supports (21) or mast arms (26-28), respectively. The bending mast (22), which is pivotably pivoted in pairs around a horizontal horizontal bending axis (28-32), can be operated remotely, and the individual drive assemblies (34-38). A control device (50, 62, 52) for controlling the movement of the mast using the adjusting member (68 to 76) attached to In large manipulator and a buffer means for buffering the mechanical vibration of the song mast (22) (82, 84, 86),
At least one of the drive assembly (34 to 38) or the mast arm (23 to 27) is at least for identifying a time-dependent measurement (Δp) derived from mechanical vibrations of the mast arm (23 to 27). One sensor (84, 86) and a buffer for generating a buffer signal, which is arranged downstream of the at least one sensor (84, 86) and whose output side is connected to the attached adjusting member (68 to 76). A unit (82) is attached,
Each drive assembly (34 to 38) has a double acting hydraulic cylinder;
The double-acting hydraulic cylinder can be energized with pressure oil via one proportional switching valve (68 to 76) each forming an associated adjusting member;
One of the double acting hydraulic cylinders is connected to the buffer unit (82) via the comparator (88) at the piston rod side end and the bottom side end of at least one double acting hydraulic cylinder. A pressure detection sensor (84, 86) is arranged as the at least one sensor (84, 86) for determining a time-dependent pressure difference as the time-dependent measurement (Δp);
Large manipulator characterized by Large manipulator according to claim 1, characterized in that the buffer unit (82) has an analog or digital high-pass filter (90, 92). Large manipulator according to claim 2, characterized in that the limiting frequencies of the high-pass filters (90, 92) attached to the individual mast arms (23-27) can be adjusted independently of each other. The large manipulator according to claim 2 or 3, characterized in that the limiting frequency of the high-pass filter (90, 92) can be adjusted according to the natural frequency of the attached mast arm (23 to 27). The large manipulator according to any one of claims 2 to 4, characterized in that the limiting frequency of the high-pass filter (90, 92) can be adjusted to a value of 0.2 Hz to 10 Hz. 6. Each of the high-pass filters is formed by a low-pass filter (90) whose input is interrupted by the output of the comparator via a comparator (92). The large manipulator according to any one of the above. The large manipulator according to any one of claims 2 to 6, characterized in that each high-pass filter (90, 92) forms an aperiodic transfer function. 8. The evaluation / safety circuit or the evaluation / safety routine (94) is arranged downstream of each high-pass filter (90, 92), according to any one of claims 2-7. Large manipulator. Evaluation and safety circuit or evaluation and safety routine (94) is an input-side output signals of both the pressure detection sensor (84, 86) (p _{s, p b),} characterized in that it is actuatable in claim 8 Large manipulator described in 1. The control device has a microcontroller (52) having a coordinate setting device (64) for controlling the adjusting members (68 to 76), and the microcontroller (52) remotely controls the input side with the bus system (63). It can be energized with movement data for mast movement via the devices (50, 64), and a transmitter for forming a buffer unit (82) is added to each adjustment member. The large-sized manipulator according to any one of claims 1 to 9, characterized in that it can be biased by a measured amount (Δp) belonging to the arm (23 to 27). A shift correction device for shift correcting the bent mast (22) is provided, and the shift correction device includes at least one solid angle detection sensor (94) or distance detection sensor disposed on one (27) of the mast arm. , A target value storage memory (96), and a comparator for controlling at least one of the adjustment members (68 to 76) connected to the target value storage memory and the output unit of the solid angle detection sensor or the distance detection sensor The large manipulator according to any one of claims 1 to 10, characterized by comprising: Large manipulator according to claim 11 , characterized in that a solid angle detection sensor or a distance detection sensor is arranged on the terminal arm (27) of the bending mast (22). 13. A large manipulator according to claim 11 or 12 , characterized in that the target value storage memory (96) can be energized by a digital output signal of a solid angle detection sensor or a distance detection sensor (94) via a control routine. . Damping the mechanical vibration of the bending mast (22) of a large manipulator in which the mast arms (23 to 27) of the bending mast (22) can be rotated relative to each other by means of one drive assembly (34 to 38), respectively. In a way to
Measuring a time-dependent measure (Δp) derived from mechanical vibrations of the mast arm in at least one of the drive assemblies (34 to 38) or in the mast arm (23 to 27) attached thereto, Processing in the buffer unit (82) as the evaluation unit to form a dynamic buffer signal and interrupting the adjusting member (68-76) controlling the drive assembly;
The drive assembly (34 to 38) is configured as a hydraulic cylinder, and a time-dependent pressure difference (Δp) between the bottom side of the hydraulic cylinder and the piston rod side is measured as a measured quantity, and a buffer unit (82 as an evaluation unit) ) To form a buffer signal,
A method characterized by. The buffer unit (82, 90, 92) is characterized by filtering a measured quantity (Δp) dynamic component equal to or greater than a predetermined limit frequency, phase shifting and / or amplifying to form a buffer signal. The method according to claim 14 . The method according to claim 15 , characterized in that the limiting frequency is set to 0.2 Hz to 10 Hz according to the mechanical natural frequency of the mast arm. When the bending mast (22) is delivered to the operating position, the inclination of the terminal arm or the distance from the ground is measured at a predetermined time interval, and compared with a target value stored in advance. 17. A method according to any one of claims 14 to 16 , characterized in that if a deviation occurs, the bending mast is subjected to additional value control by controlling at least one of the adjusting members (68 to 76). .

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